这个灰色的边怎么除去

怎么除去左边和下面灰色的边？

img


想要弄成下图：

img


css:

img


html:

img

效果图

img

源码

<html>
<head>
<title>xcSharp博客</title>
<style type="text/css">
ul{
     list-style-type: none;
     width: 300px;
}
#menu {
    padding: 0px;
    margin: 0px;
}
#menu .first{
    background-color: #E98E65;
    padding-left : 1px;
    padding-top: 5px;
    padding-bottom: 2px;
    color: black ;
    margin: 0px;
    font-size: 16px;
    font-weight : bold;
}

#menu .first li div{
    padding:5px 20px;
    background-color:lightgray;
}
#menu .second li{
    padding:5px 20px;
}
#menu .second{
    padding-top: 20px;
    padding-bottom:20px;
    padding-left : 0px;
    background-color : white;
    font-size: 14px;
    font-weight : normal;
}
a{    
    color: gray;
    text-decoration: none;
}

</style>
</head>
<body>
<div id= "menu">
<ul class="first">
<li>
    <div>注册登录</div>
    <ul class="second">
        <li>
        <a href="https://blog.csdn.net/weixin_43151418/article/details/124746163?spm=1001.2014.3001.5502">购物指南</a>
        </li>
        <li>
        <a href="https://blog.csdn.net/weixin_43151418/article/details/124746163?spm=1001.2014.3001.5502">找回登陆密码</a>
        </li>
        <li>
        <a href="https://blog.csdn.net/weixin_43151418/article/details/124746163?spm=1001.2014.3001.5502">开启支付密码</a>
        </li>
        <li>
        <a href="https://blog.csdn.net/weixin_43151418/article/details/124746163?spm=1001.2014.3001.5502">注册企业用户</a>
        </li>
        <li>
        <a href="https://blog.csdn.net/weixin_43151418/article/details/124746163?spm=1001.2014.3001.5502">账户注册</a>
        </li>
    </ul>
</li>
<li>
    <div>我的订单</div>
    <ul class="second">
        <li>
            <a href="https://blog.csdn.net/weixin_43151418/article/details/124684028?spm=1001.2014.3001.5502">购物指南</a>
        </li>
        <li>
            <a href="https://blog.csdn.net/weixin_43151418/article/details/124684028?spm=1001.2014.3001.5502">找回登陆密码</a>
        </li>
        <li>
            <a href="https://blog.csdn.net/weixin_43151418/article/details/124684028?spm=1001.2014.3001.5502">开启支付密码</a>
        </li>
        <li>
            <a href="https://blog.csdn.net/weixin_43151418/article/details/124684028?spm=1001.2014.3001.5502">注册企业用户</a>
        </li>
        <li>
            <a href="https://blog.csdn.net/weixin_43151418/article/details/124684028?spm=1001.2014.3001.5502">账户注册</a>
        </li>
    </ul>
<li>
</ul>

</body>
</html>

first中的padding-left设为0

ul{padding:0}